fix(http/ws): case insensitive connection header (denoland#11489)

The "connection" header should be case insensitive:
https://datatracker.ietf.org/doc/html/rfc7230#section-6.1

cli/tests/unit/http_test.ts

@@ -642,7 +642,7 @@ unitTest({ perms: { net: true } }, async function httpServerWebSocket() {
  const {
  response,
  websocket,
- } = await Deno.upgradeWebSocket(request);
+ } = Deno.upgradeWebSocket(request);
  websocket.onerror = () => fail();
  websocket.onmessage = (m) => {
  websocket.send(m.data);
@@ -663,6 +663,36 @@ unitTest({ perms: { net: true } }, async function httpServerWebSocket() {
  await promise;
 });
 
+unitTest(function httpUpgradeWebSocket() {
+ const request = new Request("https://deno.land/", {
+ headers: {
+ connection: "Upgrade",
+ upgrade: "websocket",
+ "sec-websocket-key": "dGhlIHNhbXBsZSBub25jZQ==",
+ },
+ });
+ const { response } = Deno.upgradeWebSocket(request);
+ assertEquals(response.status, 101);
+ assertEquals(response.headers.get("connection"), "Upgrade");
+ assertEquals(response.headers.get("upgrade"), "websocket");
+ assertEquals(
+ response.headers.get("sec-websocket-accept"),
+ "s3pPLMBiTxaQ9kYGzzhZRbK+xOo=",
+ );
+});
+
+unitTest(function httpUpgradeWebSocketLowercaseUpgradeHeader() {
+ const request = new Request("https://deno.land/", {
+ headers: {
+ connection: "upgrade",
+ upgrade: "websocket",
+ "sec-websocket-key": "dGhlIHNhbXBsZSBub25jZQ==",
+ },
+ });
+ const { response } = Deno.upgradeWebSocket(request);
+ assertEquals(response.status, 101);
+});
+
 unitTest({ perms: { net: true } }, async function httpCookieConcatenation() {
  const promise = (async () => {
  const listener = Deno.listen({ port: 4501 });

extensions/http/01_http.js

@@ -321,7 +321,7 @@
  );
  }
 
- if (request.headers.get("connection") !== "Upgrade") {
+ if (request.headers.get("connection")?.toLowerCase() !== "upgrade") {
  throw new TypeError(
  "Invalid Header: 'connection' header must be 'Upgrade'",
  );